Displays in image display devices, such as television devices, are now being shifted from conventional cathode-ray tube displays to thin displays, such as liquid crystal displays and plasma displays. With the thin displays, the thicknesses of the image display devices can be decreased. Liquid crystal panels included in the liquid crystal display devices do not emit light, and thus backlight devices are required as separate lighting devices.
A direct backlight device for directly supplying light from to a liquid crystal panel from the back is an example of such a backlight device. In this backlight device, a reflection sheet may be arranged on a light source board on which LEDs or other type of light sources are arranged.
A direct backlight device including a reflection sheet arranged on a light source board on which LED light sources are arranged is disclosed in Patent Document 1.